My 2 cents on silver... It's irrelevant. It's viral (and a retro virus at that) not bacterial, and the virus is in the nerves not on the skin. By the time you see blisters, the virus has left the scene. Silver may just kill helpful bacteria that could otherwise help keep the virus at bay. Don't try to sterilize the area, you can end up inviting yeast instead.

It's just a cut, at this point.

It can go on the skin or be ingested - I'm not saying it will kill the rash/outbreak the baby has right now, but I do believe it could prevent it from coming back. It isn't known to kill beneficial bacteria, either.